Drive circuit for magnetic stimulation

Abstract

The inventive technique includes devices and methods for generating a magnetic field. One such device may include an inductor for generating a magnetic field and a power source for providing power. Such a device may also include a semiconductor switching device that operatively couples the inductor and power source, wherein the semiconductor switching device directs power from the power source to the inductor to generate the magnetic field.

1. A magnetic stimulation device, comprising:
 an inductor for generating a magnetic field; 
 a power source for providing power; and 
 a semiconductor switching device that operatively couples the inductor and power source, wherein the semiconductor switching device directs power from the power source to the inductor to generate the magnetic field at a resonant frequency. 
 
   
   
     2. The device of  claim 1 , wherein the inductor is a ferromagnetic core stimulation coil. 
   
   
     3. The device of  claim 1 , wherein the inductor comprises a high saturation core material. 
   
   
     4. The device of  claim 1 , wherein the inductor is formed having a thin core TMS coil design. 
   
   
     5. The device of  claim 1 , wherein the inductor is formed having an air core. 
   
   
     6. The device of  claim 5 , wherein the inductor is substantially formed in any one of a figure eight shape, a circular shape, a conical shape and a double conical shape. 
   
   
     7. The device of  claim 1 , wherein the device is adapted to be substantially portable. 
   
   
     8. The device of  claim 1 , wherein the generated magnetic field is in the form of a magnetic pulse. 
   
   
     9. The device of  claim 8 , wherein the magnetic pulse has a pulse width of less than 200 μs is in duration. 
   
   
     10. The device of  claim 8 , wherein the magnetic pulse has a pulse width that is substantially 100 μs in duration. 
   
   
     11. The device of  claim 8 , wherein the magnetic pulse has at least one characteristic that is adapted to stimulate a cortical neuron. 
   
   
     12. The device of  claim 1 , wherein the power source comprises an AC power supply and a battery. 
   
   
     13. The device of  claim 1 , wherein the power source comprises a DC power supply. 
   
   
     14. The device of  claim 1 , wherein the power source comprises a battery. 
   
   
     15. The device of  claim 1 , wherein the semiconductor switching device is an Integrated Gate Commutated Thyristor (IGCT). 
   
   
     16. The device of  claim 1 , wherein the semiconductor switching device is an Insulated Gate Bipolar Transistor (IGBT). 
   
   
     17. The device of  claim 16 , further comprising a commutating diode connected to the IGBT in parallel for reducing a high voltage transient across the IGBT. 
   
   
     18. The device of  claim 1 , further comprising an energy storage device, wherein the power supply charges the energy storage device and the semiconductor switching device directs power from the power source to the inductor by causing the energy storage device to discharge into the inductor to generate the magnetic field. 
   
   
     19. The device of  claim 18 , wherein the energy storage device is at least one capacitor. 
   
   
     20. The device of  claim 18 , wherein the energy storage device is the power source. 
   
   
     21. The device of  claim 18 , wherein the energy storage device is a battery. 
   
   
     22. The device of  claim 1 , wherein the generated magnetic field is configured for one of: transcranial magnetic stimulation (TMS), repetitive transcranial magnetic stimulation (rTMS), magnetic seizure therapy (MST) and peripheral nerve stimulation. 
   
   
     23. A method, comprising:
 providing power using a power source; 
 operatively coupling the power source to an inductor using a semiconductor switching device; 
 directing power from the power source to the inductor using the semiconductor switching device; and 
 generating the magnetic field at a resonant frequency using the inductor. 
 
   
   
     24. The method of  claim 23 , wherein the inductor is a ferromagnetic core stimulation coil. 
   
   
     25. The method of  claim 23 , wherein the inductor comprises a high saturation core material. 
   
   
     26. The method of  claim 23 , wherein the inductor is formed having a thin core TMS coil design. 
   
   
     27. The method of  claim 23 , wherein the inductor is formed having an air core. 
   
   
     28. The method of  claim 27 , wherein the inductor is substantially formed in any one of a figure eight shape, a circular shape, a conical shape and a double conical shape. 
   
   
     29. The method of  claim 23 , wherein said providing, operatively coupling, directing and generating are performed by a device that is adapted to be substantially portable. 
   
   
     30. The method of  claim 23 , wherein generating a magnetic field comprises generating a magnetic pulse. 
   
   
     31. The method of  claim 23 , wherein the magnetic pulse has a pulse width of less than 200 μs is in duration. 
   
   
     32. The method of  claim 23 , wherein the magnetic pulse has a pulse width that is substantially 100 μs in duration. 
   
   
     33. The method of  claim 23 , wherein the magnetic pulse has at least one characteristic that is adapted to stimulate a cortical neuron. 
   
   
     34. The method of  claim 23 , wherein the power source comprises an AC power supply and a battery. 
   
   
     35. The method of  claim 23 , wherein the power source comprises a DC power supply. 
   
   
     36. The method of  claim 23 , wherein the power source comprises a battery. 
   
   
     37. The method of  claim 23 , further comprising charging an energy storage device using the power supply, and wherein directing power from the power source to the inductor using the semiconductor switching device comprises causing the energy storage device to discharge into the inductor to generate the magnetic field. 
   
   
     38. The method of  claim 37 , wherein the energy storage device is at least one capacitor. 
   
   
     39. The method of  claim 37 , wherein the energy storage device is the power source. 
   
   
     40. The method of  claim 37 , wherein the energy storage device is a battery. 
   
   
     41. The method of  claim 23 , wherein the generated magnetic field is configured for one of: transcranial magnetic stimulation (TMS), repetitive transcranial magnetic stimulation (rTMS), magnetic seizure therapy (MST) and peripheral nerve stimulation. 
   
   
     42. The method of  claim 23 , wherein the semiconductor switching device is an Insulated Gate Bipolar Transistor (IGBT). 
   
   
     43. The method of  claim 42 , further comprising reducing a high voltage transient across the IGBT using a commutating diode that is connected to the IGBT in parallel. 
   
   
     44. The method of  claim 23 , wherein the semiconductor switching device is an Integrated Gate Commutated Thyristor (IGCT).